Hip and thigh pain originates from the nerves exiting the spine around the small of the back. These nerves can become inflamed by pressure from bony structures or impingement from soft tissues such as muscles and spinal discs. Driving can aggravate the pain by causing swelling and pressure on the nerves that form the sciatic nerve and other nerves exiting at the level of lower spine.
Pain From Bony Structures
The body's joints are protected by cartilage, which prevents the joint's bones from rubbing together, causing pain and inflammation. When the cartilage deteriorates, the nerves become trapped between bones and produces pain. Arthritis is a common cause of this deterioration. When the lower spine or hip joints are affected, it causes pain in the hip and thigh. The National Institute of Health describes arthritis as involving the breakdown of cartilage. Cartilage normally protects the joint, allowing for smooth movement. Cartilage also absorbs shock when pressure is placed on the joint.
Soft Tissue Nerve Pain
Soft tissues such as muscles, tendons and ligaments can become inflamed and cause pressure on nerves. Muscles in the lower back and buttocks can become tight and spasm, causing pressure on the nerves leading to pain in the hip and thigh region. Prolonged stress from driving can cause this tightness, producing pain and discomfort. Frequent rest stops with stretching can help alleviate the discomfort.
Joints of the lower spine and hips have capsules that hold in the lubricating synovial fluid. When these capsules become inflamed, it's called bursitis. With bursitis, the joints begin to deteriorate from lack of lubrication. According to ThePainClinic.org, inflammation of the superficial and deep bursa produces localized pain over the trochanteric region as well as radiating pain down the outside thigh. Driving can aggravate bursitis by the application of constant pressure on the inflamed bursa. Frequent rest stops with walking can help alleviate this pain.
Hip and Thigh Pain From Discs
Bulging and inflamed spinal discs can result in hip and thigh pain. The Sciatica Clinic reports pain might only come when sitting or standing in a certain position. Clinical experience indicates that these positions are usually associated with continually holding a poor posture either at home or at work. Protruding the head forward peering at a computer all day, regularly lifting a baby out of the back of the car or driving for long periods can aggravate the condition.
Avoiding hip and thigh pain while driving might be as simple as frequent rest stops with short walks. Adjust the seat for proper posture, making sure there is nothing causing pressure on the buttock area such as a fat wallet. If the pain persist or gets unbearable, consult a doctor for evaluation of your condition.